One of the most important characteristics of a tablet formulation is its disintegration phenomenon. The disintegration time of a conventional tablet is commonly determined using United States Pharmacopoeia (USP) disintegration apparatus. However, no specific pharmacopoeial apparatus has been identified to determine the disintegration time of rapidly disintegrating tablets (RDTs). It is often difficult to precisely determine the disintegration time of RDTs using USP disintegration apparatus when the tablet disintegration process is very rapid. Moreover, USP disintegration apparatus has limitations in discriminating between disintegration times of different RDTs. Thus, it is necessary to develop a disintegration apparatus capable of determining precisely the disintegration time of RDTs.